Process for Separating Bitumen from Other Constituents in Mined, Bitumen Rich, Ore

ABSTRACT

Separation of bitumen from mined ore employs cooling of the mined ore at a temperature where all the species contained in the ore become solid and brittle. Ore is maintained solid by appropriate continuous injection of cold air and/or carbon dioxide in the processing plant through the process. Difference in thermal expansion coefficient between bitumen and other ore species creates thermal stresses at interfaces of bitumen and other materials. The stresses favor separation of bitumen from other materials along species interfaces during comminution. The breaking of existing ore particles tends to occur at interfaces between different species, creating a mix of particles where bitumen particles are not aggregated with any other ore constituents such as ice or sand particles. The particles are maintained cold, loose and unattached. Ore particles are sorted and separated while still frozen in solid phase, creating a stream of frozen bitumen particles. The process is stopped when bitumen concentration is large enough for economical treatment by other bitumen existing processing techniques.

This application claims the benefit of U.S. Provisional Application No.61/328,667, filed Apr. 28, 2010, which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

Many heavy oil, bitumen minable deposits exist around the world wherebitumen and heavy other hydrocarbons are mixed with various minerals andwater. In North America, such deposits exist in the Athabasca region andare usually cased as “the Athabasca oil sands”. Some of these depositsare shallow enough to be mined. Once the ore has been mined, thehydrocarbons need to be separated from the ore before receiving furthertreatment such as upgrading in order to transform the bitumen inmarketable synthetic crude oil [SCO].

Many processes exist and are used to perform this extraction, but theyall depend upon either mixing the ore with a warm fluid, water basedmost of the time, in order to perform this extraction, or using somesolvent mixture to dissolve the bitumen and wash the ore from it.

A commonly used process is the so called warm water process. Its outputis a bitumen froth whose concentration in mass is 60% bitumen and 30%water, and 10% water that carries the froth.

Other processes subsequently treat this product until commercialsynthetic oil [SCO] is produced and sold. Some of the downsides of thoseprocesses are the demand they make on fresh water, their cost, theirenergy requirement and the amount of liquid toxic wastes they generate,known as tailing ponds in the industry. These facts are well known andwell documented within the industry.

Problems exist and remained to be solved for recovering bitumen fromores. Needs exist for improved bitumen separation.

SUMMARY OF THE INVENTION

The invention described here is a new process that can replace the hotwater or warm water processes currently used.

This new process requires less energy than the most commonly used warmwater or hot water based processes, but most importantly requires noaddition of water or any other liquid and does not create a stream ofliquid waste. The new invention removes the need for tailing ponds.

This invention describes a new process that performs the separation ofbitumen from mined ore without requiring the use of water or otherproducts, solids or liquids.

This process take the mined ore, loosely crushed, coming from the minesite and separates bitumen from its other constituents. What comes outof the process is pure bitumen or bitumen with other impurities. Theimpurities are less than, no greater than or equivalent to those in thebitumen froth produced by the hot water or warm water processes. Theresults are something between pure bitumen and bitumen in froth that hasbeen found to be the most cost efficient output of the process.

This invention describes a process of separation of bitumen from minedore containing these bitumen.

This process is based upon cooling of the mined ore at a temperaturewhere all the species contained in the ore become solid and brittle. Orecomminution is then performed on the ore while ore is maintained solidby appropriate continuous injection of cold air and/or carbon dioxide inthe processing plant.

The ore pellets are broken in smaller parts. Because of difference inthermal expansion coefficient between bitumen and other ore species,thermal stress is created at interfaces of bitumen and other materialsthat favor separation of bitumen from other materials during thecomminution process.

Indeed because of the effect of cold temperature on matter, the breakingof existing ore particles tends to occur at interfaces between differentspecies, creating ultimately a mix of particles where bitumen is in aform of bitumen particles not aggregated with any other ore constituentssuch as ice or sand particles.

The ore particles are then sorted and separated while still frozen andin solid phase, creating ultimately as the main output of the processdescribed in this application a stream of frozen bitumen particles. Theprocess can also be stopped before pure bitumen is created, when bitumenconcentration is large enough to be economically treatable by otherexisting processing technique, such as for example a paraffinic solventunit.

When the required output quality is reached, constituents are allowed towarm or be warmed up to normal ambient temperature. Bitumen rich outputis then sent to the next processing stage whatever it is, paraffinicsolvent unit, upgrader, in order to receive further treatment, while theleftover species are disposed of as wastes.

The process described and claimed in this application does not requiremixing ore with water or any other liquid such as solvent.

This is a main feature of the invention. The process replaces thecurrently used warm water extraction process for mined oil sands.

The invention uses cold engineering. A state of the art cold plant isrequired to provide the process with cold air and/or liquid carbondioxide with optimized energy efficiency. The frozen ore is thenprocessed using comminution or size reduction techniques. Contrary totheir traditional use, these techniques are chosen and particles aresized in order to maximize phase separation between bitumen and otherspecies, while minimizing sand grain size reduction, followed by stateof the art powder handling and classification.

When bitumen has been liberated from the sand grains a complex powdermix is constituted, and effective separation of the species needs to beperformed. The powder mix created is very cohesive, in the sense thatindividual particles tend to stick to each other, creating particleaggregates that behave like bigger complex particles. The reason forthis is that some particle-particle interactions, such as for examplethe Van der Walls force, are much greater than the weight of these smallparticles. Various classifications of technology exist and can be usedin the context of a multiple step process, where each one targets theremoval of a specific kind of waste from the ore stream. The process isorganized so that the easiest particles to remove are removed first,allowing for further work to be performed on a more concentrated orestream.

The invention is based upon the integrated combination of threedifferent functions without the use of any water or solvent through theprocessing chain in order to remove enough minerals matter as well somewater from the processed ore stream to produce as a result a productwhose purity is at least comparable to the output of the warm waterprocess. Additionally the rejected waste stream can be further treatedin the same manner as the main bitumen rich ore stream in order toremove residual bitumen left over from the waste before the waste isfinally rejected from the process. This is done using the same processbut with technological implementations optimized for the composition ofeach ore or waste stream.

The initial input of the processing chain is mined oil sand ore that hasbeen prepared after removal of the biggest mineral rocks of a few cmdiameters in size or greater. The ore is put in crusher and precooled atambient air temperature. This temperature is not constant and variesdepending upon seasons and local weather conditions. The precooling isdone by forcing ambient air to flow through the ore during this crushingstage. In the event that the mined ore temperature is colder thanambient air the preliminary crushing is performed without forced airinjection in order not to warm the ore.

Depending upon the specifics of each implementation of the process,cooling gas from the refrigeration plant can also be used at thatpreliminary crushing stage.

The particle size of the ore at the end of this preparatory stage istemperature dependent, the colder the temperature the smaller the oreparticle size.

Once the ore has been prepared, it is introduced in the main processingchain and further cooled and crushed in such a way that it remains looseduring the cooling and crushing process. This is done in a mill that isfor example a ball mill through which cooling agent is forced. Coolingand separating is achieved for example by making sure the ore isagitated enough during the cooling process so that existing ore pelletscannot aggregate into bigger particles during the cooling process. Theore from the mine is cooled in a crusher that reduces the size of thepellets while they are cooled through this cooling phase. Water existingwithin the ore need to be turned into ice. The bitumen needs to becooled below the Fraass fragility point or glass transition temperatureT_(g) to become hard, solid and brittle.

This temperature threshold varies with each bitumen chemical compositionbut is usually in a range between approximately −30° C. up to −5° C.

Accordingly, the operating temperature for the process described here isbelow the glass transition temperature of the processed bitumen. Theoperating temperature range, below T_(g), is determined as part of theprocess cost efficiency/optimization.

Indeed, in order to globally optimize the process, the ore can be cooledfurther below its transition temperature to take advantage of thethermal expansion coefficient differences between heavy hydrocarbons andthe rest of the species present in the ore as well as of the increasedbrittleness of bitumen with decreasing temperature. Because of thethermal expansion differences, cooling below the temperature wherehydrocarbons become solid and brittle creates thermal stresses at theinterfaces between the hydrocarbons and the rest of the are materials,facilitating phase liberation from each other. Hydrocarbons contractmuch more than minerals or ice under cooling.

Cooling is obtained either by using cold air or solid or pressurizedliquid or gaseous carbon dioxide or a combination of both. Liquidnitrogen can be also used, but it is more expensive.

During reducing the particle size through comminution, particle size ofthe ore is reduced, and the number of particles increases accordingly.Some of these reduced size particles have a greater bitumen massfraction. Comminution can be ensured through various devices fromcrushers at the beginning of the process to prepare the mined ore beforecooling starts. When the particle sizes decrease and the species getmore and more separated, the ore stream can be aerated for furthertreatment. Mills or jet milling devices, for example, are used forfurther and finer comminution. Gas driven classifying machine, such ascyclone or forced vortex classification machines are used as well.

Also it is useful to separate the ore into different streams by particlesizes in order to perform comminution separately on each stream. Inthose cases the comminution parameters and technology are independentlyoptimized for each ore stream. For example coarser particles are treatedfurther in tumblers, while finer particles are aerated and treated in anaerosol form in a jet mill and air classifying machine. Ore istransferred from one stream to another once its properties have evolved.

Stream separation is achieved by passing initial streams through ascreen and treating the streams in parallel but with different machinesthe particles that pass through and the particles that do not passthrough the screen. The screen is washed with high pressure cold gasjets, whose velocity is high enough to separate aggregated particlesfrom each other, and accordingly cleaning coarser particles from smallerone sticking to them.

In the cooling phase description, an important feature of the describedprocess is that because of the significant difference of thermalexpansion between bitumen on the one hand and ice and most minerals onthe other, the breaking of the particles during the comminution phasewill occur preferentially at interface planes. This preferentiality willbe larger with decreasing temperature and increasing thermally inducedstresses. For each deposit, a very important step for the optimizationof the process is finding the highest operating temperature or, moreexactly, temperature range through the chain of crushing/sortingstations, where this difference of thermal expansion effect is largeenough to fully separate the bitumen particle from the rest of the ore.During the various steps of comminution the thermally induced stresshelps by making complex particles made of bitumen and other constituentssplit and break preferentially along the thermally stressed interfaces,freeing bitumen particulates from the rest of the ore.

The amount of thermal stress created of course increases the energyrequirements and the cost of cooling but will decrease the cost ofcomminution. Determining how much cooling is best is part of building aplant based upon a specific deposit and ambient condition.

Toward the end of the process, when the size of the particulates hasbeen reduced enough, most if not all of the bitumen is present in theform of a bitumen powder mixed with other ore constituents powders, suchas ice crystals and fine mineral particles.

Separating the various species when the ore is a mixture of fineparticle, bitumen being in the form of a pure bitumen powder needs to bedone while making sure that the ore remains cold enough to be solid andloose, if necessary by injecting more cold gas or liquid carbon dioxide.The separating is to be performed in several steps along the processchain between various comminution stations in order to remove wasteparticle that can be separated from the ore as early as possible, as aconsequence of the change in properties of the ore induced by thepreviously performed comminution step.

Each separation station provides as its output an ore with a higherbitumen mass fraction compared to the ore at the input of the station.

Each separation and sorting station uses an optimized principle andtechnology targeting the specific wastes to be removed.

For example, sieves or screens are used initially at the beginning, toremove coarser particles. Multiple stages of gas classification machinessuch as cyclones and forced vortex machines follow in later stages.

Once the limit of air classification to remove mineral particles hasbeen reached for removing wastes from the ore stream, additionaltechnology is put into play such as for example electrostaticprecipitators as well as other separators, depending upon otherdiscriminating properties between these species, such as for example,surface adhesive properties or electrical conductivity of the species.Pure bitumen powder is the final and ultimate output of the new processdescribed herein, all the other ore constituents having been eliminated,one by one through the various stations of the process.

The three functions will be applied sequentially or simultaneously aswell as repetitively using different devices or technologies in order toadjust to the variation in ore characteristics.

This invention allows efficient control of ore temperature such asdecreasing ore body temperature with decreasing particle size, and atthe same time increasing purity of the separated species.

Because tar sand is a natural material and has properties thatsignificantly vary from deposit to deposit, each implementation usesspecific operating parameters while keeping the fundamental principlesof the invention of solid crushing and sorting of pure mined ore broughtdown to a temperature low enough so that such treatment become possibleand selectively removing wastes along the process.

The powder mix contains very small particles, whose size is smaller thanone micron along with coarser particles. The bitumen is part of thefinest particle species in the ore, along with ice particles and verysmall mineral particles, usually clay, called fines in the industry.

The new process described in this application allows for a large rangeof practical implementations, on a continuous flow of ore or in batchmode treatment as well for some specific needs. Each project employsspecific implementation, depending upon ore conditions and requirements,but the new process always is articulated around following three actionsdetailed above applied upon the extracted ore as part of the describedprocess.

The innovative process described herein resides in a combination ofsteps to separate bitumen from all other non-bitumen species present inthe ore after the bitumen has been made solid, brittle and thermallystressed while going through the cooling process.

The combination enriches the processed ore stream by removing specificwastes one after the other until the required output concentration orpurity is achieved.

Because of the thermo-physical properties of these materials at lowtemperatures the bitumen becomes a brittle solid and then contracts muchmore than water or other minerals because its thermal expansioncoefficient is larger than that of water or silica.

The ore also contains fine minerals, such as clays. They are eitherfreed and treated as independent mineral particles as part of theprocess, or remain trapped in the species that contains them. The finematerials such as clays are very dominantly contained in water whichbecomes ice particles. Whatever impurities are present in the bitumen,whether dissolved or included with sizes smaller than the bitumen powderfinal size, are not affected by the process described herein and remainincluded in the bitumen powder, and are not removed by the use of theprocess. Those small inclusions, if any, have to be dealt withsubsequently.

The process uses several steps made of the following three independentactions that can be used together or one after the other or acombination of both, under various implementations, as part of theprocess: cooling of the ore while keeping it agitated enough so that itremains loose and the particle size does not increase during theprocess, crushing the ore in order to liberate bitumen from othermaterials present in the ore while it is cold so that bitumen and allother constituents are and remain solids and brittle through theoperation, and separating the materials while they are still cold enoughso that they remain frozen, solid and loose during the separation. Theore can be cooled even more below the temperature where the hydrocarbonbecome frozen and brittle in order to create and subsequently takeadvantage of thermally induced stress at the interfaces of thesehydrocarbons with other materials. These thermally induced stressesfacilitate the shattering process of the ore grains at the interface ofbitumen and other materials.

The crushing and separation are performed several times, each timeselecting the separation from the ore of a specific waste material,either some mineral, selected by size, typically above a certain cutoffsize set differently for each separation station, decreasing along theprocessing chain, or nature or ice. The ore is cooled with injection ofcooled liquid carbon dioxide where the liquid carbon dioxide transformsitself upon release in the ore processing chain from a part in gas forpart in carbon dioxide ice.

The carbon dioxide ice is further mixed with the ore before itssublimation occurs. The ore could also be cooled with refrigerated air.

The ore could similarly be cooled with a mixture of cold air and liquidcarbon dioxide where the liquid carbon dioxide transform itself uponrelease in the ore processing chain for a part in gas for part in carbondioxide ice.

The carbon dioxide ice is further naturally mixed with the ore beforeits sublimation occurs. The ore also is cooled with refrigerated air.

The ore is separated by grain size in two or more independent streamsthat can be treated separately for bitumen liberation. The gas expansionresulting from the heat transferred from the ore to the cooling gas isused as a mechanical driver to work on the ore stream itself.

The crushing is controlled to separate bitumen from grains, whileminimizing the crushing of sand grains and other mineral material.Cooling and agitating the ore thereby prevent particle sizes fromaggregating and maintain the ore in loose condition. Freezing theparticles makes the particles brittle.

Further cooling takes the ore below the temperature where the bitumenparticles and hydrocarbon particles become frozen and brittle. Crushingthe ore and separating fine bitumen and hydrocarbon particles fromlarger particles frees and separates fine bitumen and hydrocarbonparticles from larger particles of other materials present in the ore.

These and further and other objects and features of the invention areapparent in the disclosure, which includes the above and ongoing writtenspecification, with the claims and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of steps in purifying bitumen from ore taken froma mine.

FIG. 2 is a flow chart of a cold plant and cold distribution for the oreprocessing.

FIG. 3 shows steps in the separation of bitumen from ore.

DETAILED DESCRIPTION OF THE DRAWINGS

Without limitation, and in order to allow to someone skilled in the artto implement and optimize the process described in this application fora specific project, the following examples illustrate practicalimplementation where the elementary elements of the process are usedseveral times, each time through the use of a different technology, inorder to reach gradually pure bitumen powder. Again this is just as anexample of implementation. It must be stated that all the specificsdescribed in this section are relevant to the described example but arenot limiting to the process implementation. The example described inthis section is illustrated in the attached flowcharts.

Referring to FIGS. 1 and 2, in step 1 the ore 11 arrives from the mineand is prepared in a way similar than what is done for the warm waterextraction process. The biggest rocks are removed 13, and the remainingore is crushed to have a granular size not exceeding ˜2 mm. Dependingupon the circumstances, and the time of the year, or under operatorcontrol as shown in FIG. 2, the ore might or might not be precooledduring this step 1 stage. The cold process gas is returned throughinsulated line 141 to step 2A to pre-chill the ore in step 2A. Cold gas111 from step 2 in station 102 circulates through station 101 and step 1before the gas flows 113 back to the cold plant 100. Cold ambient airmay be circulated through station 101 in step 1. Ambient air or coolinggas can be forced through the ore during this stage.

In step 2, the ore 21 is then transferred to a set of two closed tumblermills in stations 102A and B for step 2 where in and out of gas arecontrolled and where the ore is further lightly crushed and start to becooled to its operating temperature by injection 121 of cold gas fromthe cold plant 100. The criteria for exiting station 102 is particlesize smaller than 500 μm. Ore output is performed through an integratedvibrating screen 25.

No rejection is planned at this stage, but rejection 23 is used ifsingle rocks bigger than 500 μm and smaller than 2 mm are present in theore in significant amount. Otherwise they will ultimately be reduced andpassed through. Ore output 31 temperature is what it needed to keepgrains loose without reagglomeration, for example in the −5 to −15° C.range. The temperature needs to be monitored. When atmosphericallypossible, this station 102 is air cooled with forced ambient air.

Regarding cooling gas management around step 2 in station 102, twooptions exist and are used depending upon circumstances.

a) Cooling gas 141 is flowed back through step 2 and then Step 1 instation 101 where the gas precools initial ore before being eitherreleased or recycled depending upon the specifics of the cooling systemand of the gas, air, CO2, summer, winter . . .

b) When outside temperature is cold enough atmospheric air is used tocool 101, 201 a and possibly 201 b allowing for additional energy savingduring winter time.

Transient time through the step 2 and station 102 will depend upontemperature gradient but should not exceed 2-3 minutes at most. Duringthis stage in step 2 all water included in the ore is turned into ice.The kinetic of this transition drives the time through this station. Theore at this point is in bulk with ambient/air and or cooling gas forcedthrough it while it is crushed. Its output characteristics are:

Mass in=mass out

Temperature is unknown and is not critically important as long as

a) all water is turned into ice, and

b) the granular materials are properly aerated and vibrated, andgranules do not re-agglomerate throughout treatment and transitiontoward the next step.

It is expected that the corresponding ad-hoc temperature, driven byphysical requirements, such as salt concentration in the water as wellas specific bitumen surface adhesive properties as a function oftemperature, will be in the range −15° C. to −5° C.

In step 3, the ore 31 arriving from step 2 in station 102, with afraction of the gas is subsequently tumbled and crushed while thecrushed ore is cooled down further as needed through cooling agentinjection 115. At the exit 35 of this stage the crushed ore temperaturemust be below bitumen glass transition temperature.

Cooling of the ore and liberating bitumen drives treatment time duringthis step.

The exit 35 of step 3 is through a ˜150 μm vibrating and aeratedsplitting screen 37 as seen as a one pass step with no feed back loopprovided. If needed, a two steps screen is provided to reinsert theparticles above 300 μm in size in the tumbling mill 103.

This screen separates the ore stream in two parts. The coarse part thatis noted C, and the fine part is further noted F. Most of the gas isdirected with the fines F where the cold gas is more useful. This isalso implied by the use of cooling gas for washing as much fines F aspossible from the coarse C through the splitting screen 37. The gas massflow rate must be also compatible with the ore mass flow rate throughthe screen 37, so there is no great flexibility at this stage for tuningthe gas velocity.

From this point forward, the coarse C and fine F streams are treateddifferently.

In step 4-C, the coarse part is sent to another tumbler 104C with aslightly lighter action than the previous one 103. Cold gas is injectedto maintain low operating temperature. The amount of cooling cannot belarger than the mechanical energy spent on the ore. Because this orestream C is made mostly of coarse sand grain with some non-liberatedbitumen, the liberation of bitumen is very efficient. The particlesbeing coarser and not surrounded by much small articles, liberatingbitumen from them is a more efficient process, while it is important toavoid breaking sand grains as much as possible.

Smaller particles, fines, bitumen and ice liberated by the process areextracted through a tightly coupled classification in step 4-C and aresent 41 toward the fine stream input to step 4-F. Remaining coarseparticles exit the process after a given time and are rejected as wasteafter a real time controlling unit has ensured that bitumen residual isless than an established threshold. Failing control means reinjection ofparticles with residual bitumen toward the entrance of step 4C. Verylittle residual bitumen will remain associated with these coarseparticles once properly washed with cold gas.

Step 4 C ensures that minimal size reduction for the coarse grain andminimum rejection rate.

Tuning parameters in step 4-C are intensity of the tumbling, averagepass through time in the tumbling station and classification parametersto extract fine particles, including gas velocity and size of theclassifying machine.

The classification first includes a cold gas washed vibrating screenfollowed for the fine section by a “zigzag impactor” or anotherdispersive machine in order to break aggregates, followed by a cycloneor another air classification machine. There is plenty of energyavailable in the gas stream to power the zigzag impactor and a cycloneseparator, should this technological option be selected as well as toclean the screen. The waste 47 being rejected is comprised of the coarsesection from the screen and the coarse section from the cyclone.

The output gas stream 41 from step 4-C along with the fines F passedthrough the splitting screen 37 after step 3 are then injected at theinput of Step 4-F.

This transition requires injectors that inject the ore and cold gas inthe aerated part of the process plant that will continue from here untilthe end. From this point forward mass loading ratio between injected oreand cold gas must be controlled, because classifications performancedepends upon it.

In step 4-F, the fine stream is aerated and carried away 51 from thatpoint forward with a relatively high velocity. This velocity ispermitted by the fact that the particles are small enough to haveminimal erosion effect. This fact must be enhanced by the plantconstruction that minimizes these impacts or focuses them on areasdesigned to be easy to maintain, replace or reline.

The input stream is first passed through another jet mill machine whosepurpose again is to break aggregate and also to incidentally liberateresidual bitumen through impacts against the plates before entering thenext array of classification machines. This is done just before theclassification machine so that aggregates don't have the time to reformbefore being classified.

The warming up of the cold gas through the heat transfer from the ore tothe gas provides the energy to move the stream of gas and ore throughthe various machines of this step.

The coarse section exiting from these cyclones is further aerated andinjected through another jet mill and another set of classificationmachines. The waste stream exiting is then disregarded as wastes whilethe fine section is mixed with the fine section from the first batteryof classification machines and is sent toward the next step.

This is made to ensure high quality of bitumen extraction and optimaluse of mechanical energy available in the stream due to heat transferfrom ore to gas as well as minimizing the requirements and constraintupon the next step that will be more costly.

In step 5, a high energy gas-forced vortex gas classification isperformed after fully energizing the media to break particleagglomerates.

The output quality and efficiency of this step depends upon the exactsize distribution of the fines compared to water and bitumen. Most, ifnot all mineral particles above 1 or 2 microns can be removed at thisstage.

The fines and cold gas flow to the high energy forced vortex 105 in step5 and are impacted to break apart agglomerates and send 61 largerparticles for classification 107. Larger mineral particles are rejected63, and fines are returned 65 to the input 51 of step 5.

The output product 70 of step 5 is made of initial bitumen and water,with the extraction efficiency of the process along with the residualfines that are smaller than ˜1-2 microns at most as well as the onesthat might be trapped in the ice. The corresponding amounts of mineralwill be, at most, the amount of mineral of initial size smaller than thecutoff size mentioned present in the ore.

Further product purification, possibly until pure bitumen is produced,is performed afterward to remove these fines as well as ice particles,using for example electrostatic separators to remove those residualparticles. In such a final electrostatic stage 107 water and mineralfines are removed 73 and the final bitumen output 65 is separated.

The flow diagrams summarize the process implementation as described.

As shown in FIG. 2, the cold gas plant 100 injects cold gas into severalparts of the system to cool the ore stream and subsequently control itstemperature or adjusting mass loading ratio of ore mass over gas mass inthe processing stream where needed. Secondary functions are performed bythis cold gas such as for example washing coarse particle from fineswhen needed or intermittently cleaning vibrating screens as explainedabove. The flow diagrams summarize the process implementation asdescribed.

The cold plant 100 injects 121 cold gas into initial cooling andcrushing step 2 for initial cooling of the prepared ore. The cold plant100 also injects 115 cold gas into the main inflow line 113 of theinitially crushed and cooled material flowing into the main cooling andcrushing step 3. The cold gas injection through line 115 further reducesthe temperature of the initially crushed and cooled ore and entrains thematerials into the main crushing and cooling step 3. As the cold gasimparts cooling to the materials, the gas temperature and volume risesfor driving the cold crushed materials into splitting screen 37. Thecold gas flows 35 with the particles into screen 37. The majority of thecold gas flows 123 with the fines F from the screen to step 4-F. Alesser amount of the cold gas flows 125 with coarser particles C to step4-C and back 127 to step 4-F. Cold gas is injected 131 into step 4-F.The cold gas flows 133 with the bitumen particles and ice particles tostep 5, where additional cold gas is injected 135. Cold gas flows 137with particles to step 5-C and returns 139 to the return gas flow 141 toreduce temperatures to keep particles loose in a first part of step 2.From step 2 the spent cold gas flows 111 to step 1 for cooling andloosening the ore preparation. From step 1 the used and warmed cold gasreturns 112 to the cold plant 100. The cold gas is cold air or air mixedwith CO₂ snow particles, gaseous CO₂, nitrogen or any other gas or coldgas producing product.

As shown in FIG. 3, where cooling gas is assumed to be air forillustrative purpose, loosely crushed and presorted mined ore 301arrives from a mining site at ambient temperature. The arriving ore isloose and coarse, and the particulate size is in the range 5 mm-1 cm. Ifnecessary, a preliminary crushing is performed at the entrance of theprocess to reach the desired size. The control of the particle size atthe process input is useful in order to control the cooling phaseduration. The finer the particles the faster the cooling will occur,everything else being equal.

Ore 301 is then fed to the first cooling device 303, where it is mixedwith cold air 305 from the cooling plant 100 or from outside air whenoutside temperature allows for it, while the ore is agitated. This canbe achieved either in a rotary drum or in a pipe with an air flow andair pressure large enough to ensure that the ore particles are fullyaerated and cooled through forced convection, and are not allowed toaggregate into bigger particles while they freeze. The final temperaturebefore leaving device 303 is slightly below the glass transitiontemperature, usually −30° C. or less.

Once the desired low temperature is reached, the ore is sent 307 to acomminution and gas blasting station 311 where the ore is crushed toparticulates slightly below average sand grain size. The size depends onthe deposit, but usually will be ˜100-200 micrometer. As much as ispossible and realistic, the crushing is gentle enough not to break sandgrains. Air 313 flows into station 311.

In blasting comminution station 311 frozen and thermally stressed oreparticles are projected against a hard wall or against each other at acontrolled average speed with cold air as a carrier. The output ofstation 311 is large sand grains freed from bitumen and particles,surrounded by a fine layer of ice and other particles made of bitumenand other constituents whose size are typically smaller than 150micrometers.

This ore is then fed 315 to the first separating station 317 made ofsieves and/or screens that remove the loose sand grains whose sizeexceeds 1 mm to waste 319.

The remaining ore 321 is subsequently cooled in station 323 to a lowertemperature, possibly as cold as −50 C or −40 C if needed in order toincrease the thermal stress effect and facilitate bitumen release insubsequent comminution.

The cold particles 325 are sent to a finer comminution station 327 whoseoutput average size is 5 to 10 times smaller than its input size. Thisis achieved, for example, with the use of mills. The average size of theparticles at the output 325 is ˜10 microns-20 microns or less. Very fewbigger particles are present.

Cold air 330 is delivered to further cool and maintain looseness thematerials in each station. In this illustrative example, the nextsorting station 323 discriminates by density, separating mineralsparticulates 325 with a density usually above 2 g/cc from ice crystalsand bitumen particles 337, both with a density close to 1 g/cc.

The output of station 333 is void of minerals except from those trappedin the ice particles and possibly bitumen. The bitumen is rather pure ofminerals, even fine ones, at this stage. Depending upon the requirementof the final separating steps that separates ice from hydrocarbons, theremaining ore is reduced even more in size, if that is necessary,through the use of another cooling station 341, feeding 343 anothermilling and comminution station 345.

The final separation station 351 separates bitumen particulates fromwater ice using properties discriminating between these particles. Forexample, an electrostatic separator uses the differences in conductivitybetween ice and bitumen, or a separator using the difference in surfaceproperties, such as friction or adhesive strength, discriminates betweenthese species. The output of stage 351 is waste 353 and separated purebitumen powder 355, ready to be warmed and sent toward the next step ofits treatment chain, before commercialization. From this point forward,the temperature of the bitumen powder is no longer important, and itscontrol stops accordingly.

The various coolings of the ore and the necessary control of thetemperatures during the process, from beginning to end, will be ensuredby cold gas. A cold gas generator 100 is a significant part of theextraction plant based upon this process and is also the mostsignificant energy user of this process. For ore deposits where coldwinter temperatures prevail, energy demand will be vastly reduced inwinter, owing to the advantage of the naturally cold temperature of theavailable air. Cold gas, possibly at various temperatures, will bedistributed from the plant through the full ore treatment chain thatwill use the process for bitumen extraction in order to ensure that oretemperature is what it needs to be at each step of the process. The coldair also provides the required agitating motions that ensure the oreremains loose and prevented from aggregating during the whole process.

While the invention has been described with reference to specificembodiments, modifications and variations of the invention may beconstructed without departing from the scope of the invention, which isdefined in the following claims.

1. A process for separating bitumen and other hydrocarbons from minedore that contains these hydrocarbons, based upon the applications of oneof several steps made of the following three independent actions thatcan be used together or one after the other or a combination of both,under various implementations, as part of the process cooling of the orewhile keeping it agitated enough so that it remains loose and theparticle size does not increase during the process. crushing the ore inorder to separate bitumen from other materials present in the ore whileit is cold so that bitumen and all other constituents are and remainsolids and brittle through the operation. separating the materials whilethey are still cold enough so that they remain frozen, solid and looseduring the separation
 2. The process as described in 1 where the ore iscooled even more below the temperature where the hydrocarbon becomefrozen and brittle in order to create and subsequently take advantage ofthermally induced stress at the interfaces of these hydrocarbons withother materials. These thermally induced stresses facilitate theshattering process of the ore grains at the interface of bitumen andother materials.
 3. The process as described in 1 where the crushing andseparation are performed several times, each time selecting theseparation from the ore of a specific waste material, either a specialkind of mineral particles or ice, targeting various kinds of wastematerials using different technologies or settings through the variousseparation stations deployed along the process.
 4. The process claimedin 1 where the ore is cooled with injection of cooled liquid carbondioxide where the liquid carbon dioxide transforms itself upon releasein the ore processing chain for a part in gas for part in carbon dioxideice.
 5. The process claimed in 4 where the carbon dioxide ice is furthermixed with the ore before sublimation of the carbon dioxide occurs. 6.The process claimed in 1 where the ore is cooled with refrigerated air.7. The process claimed in 1 where the ore is cooled with a mixture ofcold air and liquid carbon dioxide where the liquid carbon dioxidetransforms itself upon release in the ore processing chain for a part ingas for part in carbon dioxide ice.
 8. The process claimed in 7 wherethe carbon dioxide ice is further mixed with the ore before itssublimation occurs.
 9. The process claimed in 1 where the ore isseparated by grains size in two or more independent streams that aretreated separately for bitumen liberation.
 10. The process of claim 9,further comprising separating wastes particles from valuable ones whilekeeping the particles cold to prevent unwanted properties change inducedby warming up of the particles.
 11. The process claimed in 1 where thegas expansion resulting from the heat transferred from the ore to thecooling gas is used as a mechanical driver to work on the ore streamitself.
 12. The process claimed in 1 where the crushing is controlled toliberate bitumen from grains while minimizing the crushing of sandgrains and other mineral material.
 13. A process comprising separatingbitumen and hydrocarbons from mined ore that contains the bitumen orother hydrocarbons, further comprising cooling and agitating the ore andthereby preventing particle sizes from re-agglomeration and maintainingthe ore in loose condition, freezing the particles and making theparticles brittle, crushing the brittle particles and separating finebitumen or other hydrocarbons particles from larger particles of othermaterials present in the ore by size, density, shape, electricproperties or other surface properties.
 14. The process of claim 13,further comprising separating semi solid or fluid valuable material fromore by cooling and aerating particles of the ore, loosening theparticles, screening the particles and removing sand grains as waste,cooling and aerating loosened and screened particles to a lowertemperature milling the cooled aerated and screened particles separatingdense particles from light particles and separating and recoveringvaluable material powders from the lighter particles.
 15. The process ofclaim 14, wherein the first cooling and aerating comprises loweringtemperatures of the particles below a freezing point of water.
 16. Theprocess of claim 14, wherein the first cooling and aerating compriseslowering temperatures of the particles below a material glass transitiontemperature.
 17. The process of claim 16, wherein the looseningcomprises entraining the particles in gas jets and impacting theparticles against each other or against a solid surface.
 18. The processof claim 17, wherein the screening separates coarse mineral particlesseparated as waste and finer particles are retained and sent to the nextprocessing station.
 19. The process of claim 14, wherein the processingcomprises rotating the ore particles in drains while flowing cold gasthrough the particles.
 20. The process of claim 14, further comprisingfurther cooling and aerating the lighter particles and further millingthe cooled and aerated lighter particles before the separating andrecovering the valuable material powders.
 21. The process of claim 20further comprising separating wastes particles from valuable ones whilekeeping the particles cold to prevent unwanted properties change inducedby warming up of the particles
 22. Apparatus comprising an ore intake,ore preparation crushers and coolers connected to the ore intake, afirst cooler and loosener connected to the ore intake, an ore particlebreaker connected to the cooler and aerator, a second cooler connectedto the ore breaker, an ore particle crasher connected to the secondcooler, a particle separator connected to the second cooler, separatingcoarse particles as waste from finer particles, a particle separatorreceiving the finer particles and separating the final particles bydifferentiated surface attraction, adhesion composition, shape, electricproperties or density.